Look guys if SA ("singleplayer") wont run then samp wont get you into any servers neither. This win7 shit happened to me too BUT with a twist... i mean i installed SA last friday on my pc, played some days in the singleplayer then went on some servers in samp then i "didnt touch" SA or samp since tuesday and then i wanted to play it again today and now this shit happened.
None of the help tips helped me out i mean none of these worked for me so wtf should i do to make at least the damn singleplayer work?
BTW same shit happened to me with GTA4 too...

Edit: i have a "clear" GTA SA with the "default" version of gta_sa.exe and a Modded GTA SA with the downpatched 1.0 version of the gta_sa.exe and none of these "wants to work" with neither of the help tips wrote here